I'm running latest version of Lion and iMovie 11 (9.0.6, I think) on my i5 21" iMac with 12GB RAM. For the past few months I've had an issue with iMovie being very unstable. It sometimes crashes in the middle of working. The bigger problem is importing video from SD cards or from a folder on hard disk. I click File, Import and then I wait--sometimes it takes over an hour for the file chooser window to appear. Same thing with importing from SD cards. The window will appear but I get spinning beachball and any where from 20 minutes to hours later I can finally select the clips I want to import. I've been shooting video in iFrame format on my panny TM900 just so that I can have quick import with no conversion! That is all lost due to this issue. So far I have: Taken iMac to Apple Store, they did archive and install. Worked fine for two days, then problem came back. Created a new user account, used that for iMovie, that worked fine for few days. Deleted prefs, fixed permissions. I'm about ready to try a clean install of Lion, provided that I can redownload the installer package. Does anyone have any ideas what could be causing these incredibly slow import times?